Publications

Current Fact Sheets

Pertussis

• Pertussis [per-TUS-is] is a bacterial infection of the respiratory tract. It is also called "whooping cough."
• Pertussis is spread easily from person to person. People get pertussis by breathing in airborne droplets expelled from the nose or throat of an infected person.
• Despite an effective vaccine, pertussis continues to cause serious illness and death.
• Young children are most at risk for pertussis, but the disease is increasing in adolescents and adults.

What is pertussis?

Pertussis is a very contagious disease of the mucous membranes that line the air passages. It is also called whooping cough.

What is the infectious agent that causes pertussis?

Pertussis is caused by Bordetella pertussis, a bacterium.

Where is pertussis found?

Pertussis occurs worldwide. Pertussis bacteria live in the mouth, nose, and throat of an infected person.

How do people get pertussis?

Pertussis spreads easily from person to person. People get pertussis by breathing in droplets expelled from the nose or throat of an infected person during coughing or sneezing. It is also spread by direct contact with discharges from the nose or throat of an infected person.

What are the signs and symptoms of pertussis?

Pertussis begins as a mild upper respiratory infection. The first symptoms are like those of a cold, including sneezing, runny nose, low-grade fever, and a mild cough. Within 2 weeks, the cough becomes much worse. Children with pertussis often have episodes of rapid, spasmodic coughing followed by a characteristic intake of breath that sounds like a "whoop." The violent coughing spells are worse at night and can last for as long as 1 to 2 months. The spells can make it hard for a child to eat, drink, or even breathe. Infants under age 6 months, adolescents, and adults generally have milder symptoms without the typical whoop.

How soon after exposure do symptoms appear?

Symptoms usually appear in 5 to 10 days but can take as long as 21 days.

How is pertussis diagnosed?

Pertussis can usually be diagnosed by symptoms. The disease can be missed in persons who do not have the characteristic "whoop."

Who is at risk for pertussis?

Anyone can get pertussis, but children, especially unvaccinated or incompletely vaccinated infants under age 1 year, are most at risk.

What complications can result from pertussis?

Pertussis can result in serious complications, including middle ear infections, pneumonia, convulsions (seizures), disorders of the brain, and brief episodes of stopped breathing.

Pertussis causes about 9 deaths per year in the United States.

What is the treatment for pertussis?

Pertussis can be treated with antibiotics. Infected persons can still spread the disease until 5 days after treatment begins.

How common is pertussis?

Before the availability of pertussis vaccine, pertussis was one of the most common childhood diseases and a major cause of death in children in the United States. Since widespread use of the vaccine began, cases have decreased by 99 percent, but about 5,000 to 7,000 cases per year are still reported. In unimmunized populations in the world, pertussis remains a major health problem in children and causes an estimated 300,000 deaths per year.

Is pertussis a re-emerging infectious disease?

Yes. Despite the availability of an effective vaccine, pertussis continues to cause serious illness and death. Pertussis cases have been increasing since the 1980s, and some major outbreaks have occurred. Most cases are in unvaccinated or incompletely vaccinated infants, but cases have increased in adolescents and adults, many of whom have been immunized. This suggests that protection from pertussis vaccine may be decreasing over time.

How can pertussis be prevented?

The most important way to prevent pertussis is through complete immunization. A vaccine against pertussis has been available for many years. It is usually given to children combined with diphtheria and tetanus vaccines in a shot called DTP or DTaP. A child needs five DTP or DTaP shots, given at specified intervals, for complete protection.

As is the case with all immunizations, there are important exceptions and special circumstances. Health-care providers should have the most current information on recommendations about pertussis vaccination.

Treating infected persons with antibiotics can shorten the contagious period and prevent further spread. People who have or may have pertussis should also stay away from infants and young children until properly treated.

This fact sheet is for information only and is not meant to be used for self-diagnosis or as a substitute for consultation with a health-care provider. If you have questions about the disease described above, consult a health-care provider.

Return to Infectious Facts Index

Return to DHPE Main Page